The invention described herein is directed generally to motion picture cameras and more specifically to aperture assemblies for such cameras.
In conventional motion picture cameras, a structure known as an aperture assembly is disposed between the lens of the camera and film. The primary functions of the aperture assembly are to provide an aperture window through which the film is exposed, to hold the film in alignment with the aperture window, and to hold a film advancement mechanism, usually a shuttle claw, in registry with the film.
It will be appreciated that the aperture assembly must be made very precisely in order to hold the film and shutter claw in their desired registry. The precision in manufacture must, however, be accompanied by economy in manufacture. Toward that end, aperture assemblies have been molded to lower manufacturing expenses. Frequently, however, molded aperture assemblies do not have sufficient strength for their intended use.
Recent developments in the production of highly sensitive film have made possible the use of cameras in low light conditions without movie lamps. Such cameras generally require that the distance between the lens and the film be smaller than the corresponding distance usually found in cameras using less sensitive film. Because of this decrease in the distance between the lens and the film, the aperture assembly must be made correspondingly thinner. Prior molded aperture assemblies, already lacking in the desired degree of strength, become even weaker when their thickness must be reduced for use in cameras designed for use in low light conditions.